Fine mapping of a recessive leaf rust resistance locus on chromosome 2BS in wheat accession CH1539.

UNLABELLED

Leaf rust (LR), caused by (), is one of the most important fungal diseases of wheat worldwide. The wheat accession CH1539 showed a high level of resistance to leaf rust. A mapping population of 184 recombinant inbred lines (RILs) was developed from a cross between the resistant accession CH1539 and the susceptible cultivar SY95-71. The RILs showed segregating infection responses to Eriks. () race THK at the seedling stage. Genetic analysis showed that leaf rust resistance was controlled by a monogenic gene, and the potential locus was temporarily named . Bulked segregant analysis (BSA) using a 35 K DArTseq array located on the short arm of chromosome 2B. Subsequently, a genetic linkage map of was constructed using the developed 2BS chromosome-specific markers, and its flanking markers were and . An F subpopulation with 3619 lines was constructed by crossing the resistant and susceptible lines selected from the RIL population. The inoculation identification results showed that was recessively inherited and was fine-mapped to a 779.4-kb region between markers and at the end of 2BS. The linkage marker analysis showed that the positions of and were the same, but the identification results of the resistance spectrum indicated that the causal genes of the two might be different. The resistant materials reported in this study and the cosegregation marker can be used for marker-assisted selection breeding of leaf rust-resistant wheat cultivars.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11032-022-01318-4.